The present invention relates to a pre-assembled unit for driven axles of automotive vehicles, comprising a wheel flange, a brake disc, a wheel bearing and a synchronizing joint with an inner part, an outer part and an anti-friction bearing, the unit being adapted to be inserted into a carrier component of the automotive vehicle.
Car manufacturers are anxious to minimize the manufacturing efforts involved with the final assembly, i.e. to widely use as many pre-assembled units as possible, shifting manufacturing efforts, to the extent possible, to suppliers. Suppliers will benefit from this development in two respects. On the one hand, the increased assembly efforts incurred by them secure a higher utilization rate of their capacity and, on the other hand, their own product parts largely can be assembled in their own plant, enabling enhanced control and clearly defining the limits of liability. In this connection, a precise definition of the assembly interfaces is required for a clear limitation of liability.
In pre-assembled units of the afore-mentioned type, the assembly interface mostly is in the synchronizing joint via which the driving performance is transmitted from a driving shaft to the driven wheels. The pre-assembled unit comprises the wheel flange, the brake disc secured thereto, the wheel bearing and the outer part of the synchronizing joint in communication with the wheel hub. The said unit, during assembly, is inserted into the carrier component on the vehicle side, with the outer part of the synchronizing joint, via the anti-friction bearing, being at the same time in communication with the inner part of the synchronizing joint, which inner part, in turn, is pre-assembled on the vehicle side. It is readily apparent that this assembling step involves great efforts and requires substantial skill because two anti-friction fits are involved the precise dimensional coordination of which is of a substantial significance for the smooth operation of the unit during operation of the automotive vehicle.
Conventional pre-assembled units of the afore-mentioned type having a mounting interface in the synchronizing joint involve the disadvantage that the sleeve required for sealing the synchronizing joint can only be mounted at the end of the assembling operation which in view of the tight space conditions, frequently, is not easy. But substantial care is required because the life of the synchronizing joint to a high degree is dependent on the precisely mounted sealing sleeve.
In view of the afore-mentioned defects involved with preassembled units of the afore-described type it is the object of the invention to so improve such units that assembly thereof is substantially simplified, rendering available a unit better closed in itself and not involving any problems in handling the final assembly.